using System;
using System.Data;
using System.Data.Common;
using System.Data.Odbc;

namespace BLToolkit.Data.DataProvider
{
    /// <summary>
    /// Implements access to the Data Provider for ODBC.
    /// </summary>
    /// <remarks>
    /// See the <see cref="DbManager.AddDataProvider(DataProviderBase)"/> method to find an example.
    /// </remarks>
    /// <seealso cref="DbManager.AddDataProvider(DataProviderBase)">AddDataManager Method</seealso>
    public class OdbcDataProvider: DataProviderBase
    {
        /// <summary>
        /// Creates the database connection object.
        /// </summary>
        /// <remarks>
        /// See the <see cref="DbManager.AddDataProvider(DataProviderBase)"/> method to find an example.
        /// </remarks>
        /// <seealso cref="DbManager.AddDataProvider(DataProviderBase)">AddDataManager Method</seealso>
        /// <returns>The database connection object.</returns>
        public override IDbConnection CreateConnectionObject()
        {
            return new OdbcConnection();
        }

        /// <summary>
        /// Creates the data adapter object.
        /// </summary>
        /// <remarks>
        /// See the <see cref="DbManager.AddDataProvider(DataProviderBase)"/> method to find an example.
        /// </remarks>
        /// <seealso cref="DbManager.AddDataProvider(DataProviderBase)">AddDataManager Method</seealso>
        /// <returns>A data adapter object.</returns>
        public override DbDataAdapter CreateDataAdapterObject()
        {
            return new OdbcDataAdapter();
        }

        /// <summary>
        /// Populates the specified <see cref="IDbCommand"/> object's Parameters collection with 
        /// parameter information for the stored procedure specified in the <see cref="IDbCommand"/>.
        /// </summary>
        /// <remarks>
        /// See the <see cref="DbManager.AddDataProvider(DataProviderBase)"/> method to find an example.
        /// </remarks>
        /// <seealso cref="DbManager.AddDataProvider(DataProviderBase)">AddDataManager Method</seealso>
        /// <param name="command">The <see cref="IDbCommand"/> referencing the stored procedure for which the parameter
        /// information is to be derived. The derived parameters will be populated into 
        /// the Parameters of this command.</param>
        public override bool DeriveParameters(IDbCommand command)
        {
            OdbcCommandBuilder.DeriveParameters((OdbcCommand)command);
            return true;
        }

        public override object Convert(object value, ConvertType convertType)
        {
            switch (convertType)
            {
                case ConvertType.ExceptionToErrorNumber:
                    if (value is OdbcException)
                    {
                        OdbcException ex = (OdbcException)value;
                        if (ex.Errors.Count > 0)
                            return ex.Errors[0].NativeError;
                    }
                    break;
            }

            return base.Convert(value, convertType);
        }

        /// <summary>
        /// Returns connection type.
        /// </summary>
        /// <remarks>
        /// See the <see cref="DbManager.AddDataProvider(DataProviderBase)"/> method to find an example.
        /// </remarks>
        /// <seealso cref="DbManager.AddDataProvider(DataProviderBase)">AddDataManager Method</seealso>
        /// <value>An instance of the <see cref="Type"/> class.</value>
        public override Type ConnectionType
        {
            get { return typeof(OdbcConnection); }
        }

        public const string NameString = DataProvider.ProviderName.Odbc;

        /// <summary>
        /// Returns the data provider name.
        /// </summary>
        /// <remarks>
        /// See the <see cref="DbManager.AddDataProvider(DataProviderBase)"/> method to find an example.
        /// </remarks>
        /// <seealso cref="DbManager.AddDataProvider(DataProviderBase)">AddDataProvider Method</seealso>
        /// <value>Data provider name.</value>
        public override string Name
        {
            get { return NameString; }
        }
    }
}